He should have written and published the first half (which stands on its own), thereby forcing himself to slow down and think before writing and publishing the second half (which is a mash of brilliant but incomplete ideas which do not stand on their own, with or without the first half).
Still and all, I admire that he is willing to experiment. Other than his works keep getting longer (I crave short shories, dammit), Stephenson does not appear to be in a rut.
Which is unusual: most writers have one story to tell, over and over, and if they are gifted they find diverse ways to engage our attention.
Frank Herbert? Rut. And no engaging stylist: apart from putting science into science fiction, his primary gift to literature is the epigraph.
John Varley? Christ, I love, I adore his early short stories – nothing finer – but I couldn’t bear Steel Beech … it’s got all the same short story ideas bloated up in a big “I can write as many words as I want” uber-novel-cake.
Stephenson? Stepheson keep confounding his readers with … well, call it what you will.
Agreed 100%. Seveneves could easily have been split into half, with especially the second half being given a fuller treatment instead of… I’ve already blocked the MacGuffin there. Fall has that same approach to a detailed set building and stage dressing portion, followed by a hurried WTFedness. The rushed ending chapter of previous books is now a plot salad, half a volume long… and evidently editors aren’t calling him on it, or just bottom out after 500 pages.